Dublin Airport airbrige collapsed, damaging American Airlines Boeing 787 | Hacker News Reader

Dublin Airport airbrige collapsed, damaging American Airlines Boeing 787

aviationa2z.com

77 pointsmikequinlan47 comments

When you're getting on the plane, if you look down and to the right there's a little wheel resting against the side of the plane and connected to the skybridge. It says do not touch. That's because it's the sensor that allows the skybridge to automatically level itself when the plane moves up and down on its suspension due to fueling, loading, unloading, etc. I wonder if this is what happens if it gets touched?

I always figured it was a pinching hazard.

If you look down you also see how far away the ground is.

Always find myself subconsciously wondering how to react if the bridge/plane somehow separate.

Ride either of them down, preferably the plane. Don’t fall out!

I hate the moment of having one foot on plane, one on bridge.

Jump with both feet.

Then you probably won't enjoy watching video footage of elevator failures.

I'm fine with that, but I rode in a boat a couple times, and the first step in/out from the pier was a doozy! Aircraft don't bob and float in the surf!

I still remember old trains where you could look down and see the track while stepping from one carriage to the next. Child me always thought it was cool.

Jump forward, either into the plane or into the bridge, or rest on the back foot? I think that either we train reflexes or our body will take a guess but who trains for that?

Judging from the photos, not unless "touched" means "was pulled back and rolled about 7 turns downward".

Another design to accomplish this same goal seems to be called the "safety shoe" [1]. I believe this is a horizontal bar placed under the open door which moves the airbridge down if it gets too close.

https://www.youtube.com/watch?v=4Ir5b0GzfiE

I've wondered what that is when seeing it during boarding! The video doesn't explain anything though... Is it some proximity sensor? How? It doesn't seem to require extremely accurate positioning.

I found a product manual [1] from one manufacturer which describes stepping on it as part of a maintenance test (bottom of page 6), so it seems like some type of switch or pressure.

The idea seems to be that if the door touches the top of the sensor, it automatically lowers the jetbridge a few inches to prevent the door from being damaged. And I guess this can happen if the plane is being loaded improperly causing it to shift.

[1] PDF, 4MB: https://www.acesincusa.com/wp-content/uploads/2020/07/Safety...

Oh, I see, thanks for that! Yes it looks like a contact strip sensor kind of thing.

I have also noticed in some jet bridges, you will see some kind of air sensor probe on the end of a coiled cord, which is very odd to me that this would inform the operation of the bridge. I can't find a photo of it readily, but it is definitely something I have noticed and puzzled about.

The wheel is the primary sensor and the safety shoe is a backup.

Sometimes it doesn't have the warning and I think it should be mandatory. Any passenger can go and play with the wheel and wreck havoc.

I would hope / imagine that the amount of force necessary to move that wheel is well greater than what an average person could exert without being noticed and stopped by one of the crew! (i.e. only genuinely large movements of the 2 very heavy objects involved)

Aren't those reachable by boarding passengers? Never put anything sensitive like that near passengers. With millions of passengers, including kids, walking by it each day, someone is going to touch it for fun, especially when you put up a sign saying "touch me!"

This tech is on thousands of bridges around the world, has been for a lot of years now, and yes, millions of people have passed it, and we haven't heard of any incidents of passengers touching it and causing big issues... so I would say whoever engineered it knew what they were doing and don't need the Internet commenter expert knowledge...

I work in aviation and have moved that wheel out of curiosity. As expected, the jet bridge moved up and down with the wheel!

> That's because it's the sensor that allows the skybridge to automatically level itself when the plane moves up and down on its suspension due to fueling, loading, unloading, etc.

And if you pay attention while you're on the jetbridge, it's not entirely uncommon to feel it move as it adjusts. (Although I find the movement a bit disconcerting, even though I know it's normal.)

This sucks but it is not that big of a deal

Jet bridges can fail that way and doors get ripped off exactly to not make a bigger mess in that case

Insurance, maintenance, etc are all there for a reason. Plane should be back into service soon

> This sucks but it is not that big of a deal

Not this time, thankfully.

But it could have severely injured or even killed someone in / under the bridge at the time of failure. Especially if they were transitioning between the plane and the bridge.

If you stand below without a hardhat (as the people in the picture) you might be hit by the falling door or the airbridge itself. That might be bad.

For passengers this doesn't look particularly dangerous though. From the picture s it look like a 2 meter/6 feet fall onto concrete. Unprepared, but feet first. Sure you can die from that if you are uncoordinated and somewhat frail (e.g. suffering from osteoporosis), but most people would get away from that with a couple scratches on their hands and knees.

I could be mistaken, but I think the following are also possible:

(a) While crossing the threshold, head trauma from the bar(s) that support the flexible ceiling of the bridge.

(b) While crossing the threshold, pinned and crushed by that bar. I.e., half of their body is inside the plane, the other half is holding up the bridge via that bar.

(c) While crossing the threshold, a parent carrying a baby. Baby is ripped out of parent's arms, and falls 6-8 feet to the ground. Possibly head first.

All are horrifying possibilities, which I don't believe would be fully remediated by post-incident insurance or maintenance.

This is all under the assumption that this was a sudden collapse while the jet-bridge was fully loaded with people.

If the system just lost hydraulic pressure slowly during a non-loading time, its entirely possible that it took quite a while to collapse, and no one was near enough to do anything. The forces would be high, but there would be ample time for a human to move.

A DFW Airport maintenance employee was killed after falling from a Jet Bridge back in 2015.

reminded me of Top Gear scene

That would not happen here since it stayed pressed against the fuselage. Falling out of an open jetbridge unexpectedly has head injury written all over it. A failing / falling jetbridge has hydraulic slow descent vibes.

They are hydraulic elevators. Failure falls are slow. There are exclusion zones under the bridge, and soneone inside would have to trip, fall, and hit their head to be at serious risk.

Basically, failure modes for aviation related technology tries to take into account public risk.

This website is as ad-infested as it gets…

Wouldn't surprise me if the article itself was "AI" generated with minimal editing by a non-native English speaker, given the very awkward wording, inconsistent terminology, and repetition of key facts.

“Repetition of key facts” is something AI chatbots and pre-AI “journalists” have in common. Gotta write that ten paragraph article even though you only have one sentence of actual information.

Also what happens when info if only available from one tweet but you need paragraphs and multiple embeds.

The photo has the look of some hydraulics in the support legs failing and allowing the end of the bridge to fall.

I went to Ireland just last month, and I have to say that the Airport was significantly better than what it was 2 years ago. This news puts a damper on my raised expectations.

One incident lowers your opinion of a busy international airport?

Ummmm, yes? How often does such incident happen? Seems like not that often. I don't remember ever hearing of such incident.

I would be a lot more worried about runway incursions.. You know, like the 7 that have happened so far this year in the US..

You likely just went through the newer terminal 2 that time but it's been open 13 years already.

Also depends how exact 2 years ago is. From the beginning of covid until a few months ago it was quite understaffed as they didn't bother keeping staff training/certifications up to date as they didn't expect demand to pick up so quickly as it has.

I have to say that pre-covid, Dublin airport has been one of the better airports in my experience. Security was among the fastest of airports I've been in, decent variety of shops behind it, flights departing smoothly

I've been on some mighty rusty unstable feeling jetbridges, I've always wondered how often they collapse, and what their nominal lifetime is.

That airplane is surely not going anywhere any time soon, but it seems we have far different ideas of “severely damaged.”

Yeah, the door's on the ground. "Might need to be grounded for maintenance" sounds like something from "The front fell off" in this situation.

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